The agouti-related protein (AgRP) produced in the brain is a potent appetite stimulant. AgRP binds with high affinity to melanocortin (MC) receptors and plays a central role in energy balance by stimulating feeding and decreasing energy expenditure. This modified AgRP invention provides unexpectedly superior results when used as an appetite stimulant. AgRP animal models have successfully demonstrated enhanced feeding for an extended period, longer acting than any other known hormone or drug used to treat diseases such as cachexia or anorexia.